Circuit making and breaking device.



No. 728,820. PATENTED MAY 19 1903.,

A. J. WURTS,

CIRCUIT MAKING AND BREAKING DEVICE.

APPLICATION FILED APR. 17, 1901.

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UNITED STATES Patented May 19, 1903.

PATENT OFFICE.

ALEXANDER JAY l/VURTS, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO GEORGE WESTINGHOUSE, OF PITTSBURG, PENNSYLVANIA.

CIRCUIT MAKING AND BREAKING DEVICE.

SPECIFICATION forming part of Letters Patent No. 728,820, dated May 19, 1903.

Application filed April 17, 1901. Serial 110-56333. (No model.)

To all whom it may concern.-

Beit known that LALEXANDER J AY WURTS, a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of 5 Pennsylvania,have invented anewand useful Improvementin CircuitMakingaudBreaking Devices, of which the following is a specificatron.

My invention relates to making and breaking devices for electric circuits, and has particular reference to devices of this general character that are employed in connection with alternating-current circuits, though not necessarily restricted to this specific relation.

x The object of myinvention is to provide an automatic cut-out that shall be operated by gravity to close an electric circuit and electromagnetically to open such circuit and which shall be maintained in these positions by gravity and magnetism, respectively, without the production of noise whatever may be the kind of current employed or the frequency of alternations, if alternating current be employed.

My invention was primarily designed for use in connection with electric lamps of the type in which the light-emitting members or glowers are non-conductors when cold and are raised to conducting temperature by means of electric heaters located in proximity thereto; but it is. susceptible of use in other relations and is therefore not necessarily restricted to employment in connection with electric lamps.

More or less difficulty has been experienced in connection with heater cut-outs for lamps of the character indicated when operated by alternating currents by reason of the noise produced by vibration of the movable members of the cut-outs under the action of the alternating currents. This has been particularly noticeable and troublesome where the rate of alternations has been relatively low-- as, for example, in connection with circuits of three thousand alternations or less per minute. The cut-out devices for use in such relations are necessarily operated by a comparatively small amount of energy and in order to operate satisfactorily must be sensitive. Since the movable parts are so mounted as to be readily actuated, they are espeother, of a modified form ofcut-ou't.

cially liable to vibration. Heretofore in cutouts that have been actuated either in whole or in part by gravity to close electric circuits and electromagneticallyto open them the magnetic pull has been upwardly, whereby the movable members have been lifted from their circuit-closing positions. With such an arrangement the intermittent action of the magnetic pull due to alternating currents of low frequency is liable to result in such movement of parts as will produce a. humming or rattling noise that is objectionable and which it is the chief object of my present invention to obviate. Ihave accordinglydevisedacutout comprising a magnet and a pendent armature so disposed that the line of magnetic pull and the line of'gravity pull upon the latter make only a small angle with each other. By suspending the armature or mov- 7o able member of the cut-out so that the angle between the lines of magnetic and gravity pull is small the tendency to move from opencircuit to closed-circuit position is so reduced as to obviate noisy vibrations.

In the accompanying drawings, Figure 1 is a View, partially in side elevation, partially in section, and partially diagrammatic, of a lamp having a heater cut-out constructed in accordance with my invention. Fig. 2 is a view in elevation of the cut-out shown in Fig.

1, the view being at right angles to that of Fig.

1. Figs. 3 and 4 are plan views of the cut-out shown in Figs. 1 and 2 and respectively illustratethe movable member inclosed and in open circuit position. Figs. 5and 6 are side elevation views, taken at right angles to each I Fig. 7

is a view similar to Fig. 1, but showing a further modification. Figs. 8 and 9 are side ele- 9o vations of two slightly-different embodiments of another modification. Fig. 10 is a View,

partially in elevation and partially in section,

of a portion of the devices shown in Fig. 8.

Referring now particularly to Figs. 1 to 4,

inclusive, the'glower 1, heater 2, andballast 3 may be of usual construction and connected to the supply-conductors 4 and 5in the usual manner. The cut-out here shown comprises a base-plate 6, preferably of insulating mate- I00 rial, on which is supported a magnet-coil 7,

having a core 8 provided at its bottom with a laterally-projecting pole-piece 9 and at its top with a laterally-projecting pole-piece 10, of magnetizable material. Fastened to the polepiece 10 is a pendent flexible strip 11, of steel or other suitable conducting material, that supports an armature 12,0f magnetizable material, the lowerijend of which is located in proximity to the end of the pole-piece 9. The armature 12 may be provided with a contact button or piece 13,which is preferably,though not necessarily,of silver, forengagement with a stationary terminal piece 14, which is also preferably of silver or similar material and which projects from a terminal post or block 15, supported upon the base 6.

In order to insure the closing of the circuit by the action of 'gravity'when the magnet is deenergized, I provide the lower end of the armature 12 with two horns 16, of non-magnetic material, which, as shown, almost encircle the coil 7, though of course the form and dimensions of these counterweights are immaterial, provided the parts are of sufficient weight and are properly disposed to effect the desired result. It will be seen that with this construction there is a very small angle between the extreme positions of the armature l2 and that the armature has therefore onlya slight tendency to move to circuitclosing position while the magnet is energized, even though the magnetizing-current have a low rate of alternations.

In Fig. 5 the base 6, coil 7, pole-pieces 9 and 10, contact terminal button 13, contact-piece 14, and post 15 have substantially the same construction and arrangement as the corresponding parts shown in the preceding figures. In this modification, however,the pendent flexible strip 11 is of such length that its lower end is in proximity to the free end of the pole-piece 9 and it is provided with blocks or weights 17, of magnetizable material. These blocks or weights may be all disposed upon the inner side of the strip 11 or they may be placed on both sides and alternating with each other, as indicated in Figs. 5 and 6. A preponderance of weight on the inner side is desirable, however, in order that the strip may move outward under the action of gravity. With this arrangement of apparatus there is such interference of vibrations, due to the alternations of the current, as will keep the armature steady when deflected by the magnet.

In Fig. 7 the general structure and arrangement of parts is the same as in the preceding figures, except that the armature 18 is pivotally mounted upon a pole-piece bracket 19 at the top of the magnet-coil 7 and is provided with a non-magnetic counterweight 20, that serves to move the lower end outward when the magnet is deenergized to bring the contact-button 13 into engagement with the stationary contact-piece 14 In this arrangement the pole-piece 9, projecting from the lower end of the core 8, is shown as longer than the corresponding pole-piece 9 in the other figures; but the general arrangement of parts is the same as in the structures al} ready described, the armature being pendent and the angle of movement small-1'. 8., ma} terially less than ninety degrees. j

In Fig. 8 the armature 21 is pivotally supported in the bifurcated end of the upper polepiece 1 0, and its lower part is offset toward the magnet-coil with reference to its upper part, so. as to itself constitute a counterweight for moving its contact-button 13 into engagement with the stationary contact-piece 14.

The construction shown in Fig. 9 is the same as that shown in Fig. 8, except that the armature 22 is not bent or offset as is the armature 21 of Fig. 8. In this form, however, the armature is so hung upon its pivot with reference to the contact terminal piece 14 that gravity will swing it through the very small angle necessary to close the circuit when the magnet is deenergized.

In Fig. 10 I have shown a preferred form of pivotal support for the armatures of Figs. 8 and 9, in which the pivot 23 is a screwthreaded silver pin and the armature 21 or 22, as the case may be, is provided with a silver bushing 24. This employment of a silver pin and bushing insures good electrical contact between the best of conducting materials, and the screw-threading of the pivot prevents the armature from moving edgewise, and thus engaging with either fork of the supporting pole-piece.

It will be observed that in each of the forms shown the armature is suspended so that it is not lifted by the magnet and the angle between lines of magnetic and gravity pull is less than ninety degrees.

My invention is obviously susceptible of embodimentin other forms of apparatus, and I therefore desire and intend to include within the scope of my invention any and all modifications of what is shown and described that operate in substantially the same way to produce the same result.

I claim as my invention- 1. An electromagnetic cut-out, having a magnetizable member suspended and solely supported from one end and normally held in circuit-closing position by gravity, in combination with a magnet the field of which acts upon said member to effect a downward pull and to hold it entirely free from all contact except at the point or points of suspension.

2. In a gravity-restrained electromagnetic cut-out, the combination with a coil, of a movable member suspended and solely supported from one end and so disposed that the magnetic pull is downward and serves to hold said member freely suspended.

3. In an electromagnetic cut-out, the combination with a coil, of a circuit making and breaking member suspended and solely supported from one end and so disposed that the angle between the lines of magnetic and gravity pull thereon is less than ninety degrees and themagnetic pull serves to hold said member freely suspended.

4. In an electromagnetic cut-out, the combination with an electromagnet and a stationary contact-terminal, of a contact member suspended and solely supported from one end and actuated by gravity to close the circuit and by magnetism to open the circuit and so disposed that the angle between the lines of magnetic and gravity pull thereon is less than ninety degrees and the magnetic pull serves to hold said member freely suspended.

5. In an electromagnetic cut-out, the combination with an electromagnet and a stationary contact-terminal, of an armature suspended and solely supported from one end and held in engagement with the stationary contact-terminal by gravity when the magnet is deenergized and movable by the pull of the magnet, when energized, through an angle of less than ninety degrees to a position in which it is free from mechanical contact except at the point of suspension.

6. In an electromagnetic cut-out, the combination with a magnetcoil having laterally-projecting pole-pieces at its respective ends, of an armature pivotally suspended from one of said pole-pieces and a stationary contact-terminal so disposed as to be engaged by said armature under the action of gravity when the magnet is denergized, said armature being movable under the action of magnetism through an angle of less than ninety degrees to a position in which it is free from mechanical contact except at the point of suspension when the magnet is energized.

7. In an electric lamp of the type described, the combination with a heater-circuit, of an electromagnetic cut-out having a circuit making and breaking member which is suspended and solely supported from one end and is actuated by gravity to close the circuit and by magnetism to open the circuit, the angle of movement being less than ninety degrees and the open-circuit position being such as to free the member from all mechanical contact except at the point of suspension.

8. In an electric lamp of the type described, the combination with a glower and a heater, of means for interrupting the heater-circuit when the glower becomes conductive, comprising an electromagnet having laterallyprojecting pole-pieces, a stationary contactterminal, an armature suspended from one of the pole-pieces and movable by gravity into engagementwith said terminal when the magnet is decnergized and movable by the magnet, when energized, through a small angle to and held in a circuit-breaking position in which it is free from all mechanical contact except at its point .of suspension.

9. In a cut-out, the combination with an electromagnet and a stationary contact-terminal, of a circuit making and breaking armature having a suspension-support only, so as to be normally held in circuit-closing position by gravity and freely suspended in opencircuit position and without mechanical contact except at the point of suspension, when magnetized.

In testimony whereof I have hereunto subscribed my name this lOth day of April, 1901.

ALEXANDER JAY WURTS.

Witnesses:

JAMES B. YOUNG, WEsLEY G. CARR. 

